The invention relates generally to a seam bracket for ensuring electrical contact between different structural components in an EMI shielded structure.
The operation of an electronic device may be interrupted or hindered by electromagnetic interference (“EMI”), which is radiated or conducted energy that adversely affects the performance of circuits in the electronic device. Many different types of electronic devices are susceptible to EMI and must be shielded to maintain proper performance. In military applications, this requires the use of EMI shielded shelters for housing important electronic equipment used to control military operations. This requirement transfers to the field where mobile command centers must also have the necessary EMI shielding to prevent disruption in the event of an electromagnetic pulse event.
One strategy for providing EMI shielding involves maintaining electrical contact between the several disparate structural components in a structure. If electrical contact can be maintained between the separate components, and the external surface of the three-dimensional structure is a single conductive surface, the interior of the structure will be shielded from outside EMI and radiation of EMI from the interior of the shelter. In physics, this is referred to as a “Faraday Cage.” Although a perfect Faraday Cage cannot be obtained in nature, current designs have attempted to create structures with similar characteristics.
Especially in military applications, the current designs and methods for providing external EMI shielding have many drawbacks. The two main methods for providing EMI shielding along the edge-to-edge connections in structures include the use of “flame spraying,” EMI caulk, or a combination of both. Flame spraying involves the generation of a high energy plasma arc that ‘sprays’ droplets of melted metals (molybdenum and tin) onto the adjoining surfaces to bridge the electrical conductivity of the surfaces. However, the process is expensive, time intensive, dangerous for workers, and environmentally unfriendly. The process of using EMI caulk involves the application of a paste, consisting of solvents, a rubberized base material, and an emulsion of silver particles. However, the drawback of EMI caulk is that small quantities of the material are very expensive. Moreover, both methods may be unreliable in the field when an EMI shielded structure may need to moved from location to location over rough terrain. The bonds created along the edge-to-edge connections are sometimes brittle, and may separate, requiring additional applications of flame spraying or EMI caulk.
Therefore, an object of the present invention is to provide a device for use in providing EMI shielded structures that is helpful in maintaining electrical contact and lowering electrical resistance between separate structural components in a structure, that is reliable, sturdy and inexpensive.
Accordingly, the invention provides an illustrative seam bracket, that overcome the disadvantages of known devices while offering features not present in known devices. Although certain deficiencies in the related art are described in this background discussion and elsewhere, it will be understood that these deficiencies were not necessarily heretofore recognized or known as deficiencies. Furthermore, it will be understood that, to the extent that one or more of the deficiencies described herein may be found in an embodiment of the claimed invention, the presence of such deficiencies does not detract from the novelty or non-obviousness of the invention or remove the embodiment from the scope of the claimed invention.